<!DOCTYPE html>
<html lang="ZC">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style type="text/css">
        .grid {
            margin: auto;
            width: 530px;
            text-align: center;
        }

        .grid table {
            border-top: 1px solid #C2D89A;
            width: 100%;
            border-collapse: collapse;
        }

        .grid th,
        td {
            padding: 10;
            border: 1px solid #C2D89A;
            height: 35px;
            line-height: 35px;
        }

        .grid th {
            background-color: #638fa8;
        }

        .grid .book {
            padding-bottom: 10px;
            padding-top: 5px;
            background-color: #638fa8;
        }

        .grid .total {
            height: 30px;
            line-height: 30px;
            background-color: #638fa8;
            border-top: 1px solid #C2D89A;
        }
    </style>
    <script src="https://cdn.bootcdn.net/ajax/libs/vue/2.6.9/vue.min.js"></script>
</head>

<body>
    <div id="app">
        <div class="grid">
            <div>
                <h1>TodoList</h1>
                <div class="book">
                    <div>
                        <label for="id">
                            编号：
                        </label>
                        <input type="text" id="id" v-model='id' :disabled="flag">
                        <label for="name">
                            名称：
                        </label>
                        <input type="text" id="name" v-model='name'>
                        <button @click='handle' :disabled="submitFlag">提交</button>
                    </div>
                </div>
            </div>
            <div class="total">
                <span>图书总数：</span>
                <span>{{total}}</span>
            </div>
            <table>
                <thead>
                    <tr>
                        <th>编号</th>
                        <th>名称</th>
                        <th>操作</th>
                    </tr>
                </thead>
                <tbody>
                    <tr :key='item.id' v-for='item in books'>
                        <td>{{item.id}}</td>
                        <td>{{item.name}}</td>
                        <td>
                            <a href="" @click.prevent='toEdit(item.id)'>修改</a>
                            <span>|</span>
                            <a href="" @click.prevent='deleteBook(item.id)'>删除</a>
                        </td>
                    </tr>
                </tbody>
            </table>
        </div>
    </div>
    <script>
        let vm = new Vue({
            el: "#app",
            data: {
                flag: false,
                submitFlag: false,
                id: '',
                name: '',
                books: [{
                    id: 1,
                    name: '白夜行',
                }, {
                    id: 2,
                    name: '如何成为一个怪物',
                }, {
                    id: 3,
                    name: '嫌疑人X的救赎',
                }, {
                    id: 4,
                    name: '候场',
                }]
            },
            methods: {
                handle: function () {
                    if (this.flag) {
                        // 编辑图书
                        // 根据当前的ID去更新数组中对应的数据
                        this.books.some((item) => {
                            if (item.id == this.id) {
                                item.name = this.name;
                                return true;
                            }
                        });
                        this.flag = false;
                    } else {
                        // 添加图书
                        var book = {};
                        book.id = this.id;
                        book.name = this.name;
                        book.date = '';
                        this.books.push(book);
                        // 清空表单
                        this.id = '';
                        this.name = '';
                    }
                    // 清空表单
                    this.id = '';
                    this.name = '';
                },
                toEdit: function (id) {
                    // 禁止修改ID
                    this.flag = true;
                    console.log(id)
                    // 根据ID查询出要编辑的数据
                    var book = this.books.filter(function (item) {
                        return item.id == id;
                    });
                    console.log(book)
                    // 把获取到的信息填充到表单
                    this.id = book[0].id;
                    this.name = book[0].name;
                },
                deleteBook: function (id) {
                    // 删除图书
                    let i = this.books.findIndex(function (item) {
                        return item.id == id;
                    });
                    // 根据索引删除数组元素
                    this.books.splice(i, 1);
                }
            },
            computed: {
                total: function () {
                    // 计算图书的总数
                    return this.books.length;
                }
            },
            watch: {
                name: function (val) {
                    // 验证图书名称是否已经存在
                    var flag = this.books.some(function (item) {
                        return item.name == val;
                    });
                    if (flag) {
                        // 图书名称存在
                        this.submitFlag = true;
                    } else {
                        // 图书名称不存在
                        this.submitFlag = false;
                    }
                }
            }
        })
    </script>
</body>

</html>